The majority of condensation within a home is created by lifestyle. The level is the sum of external air plus the moisture generated within the property.
A building normally buffers high humidity, which often trigger condensation in the home provided it is a short time. Some modern materials, which now make up our home reduce its moisture buffering ability.
Severe condensation is caused when the interior atmosphere starts to get out of balance and humidity levels remain high (+70%RH) for long periods of time.
I suggest that you have an inspection carried out to help with diagnosis and producing an action plan.
In a nutshell, balanced heating and the correct ventilation at water production points will lower the level of moisture in your home.
The young, elderly or anyone with a compromised immune system, should avoid areas affected by mould growth or dampness. It is not a good idea to sleep in any room affected by mould growth unless the area has been properly cleaned.
To minimise condensation, maintain the ambient temperature above 15oC and ideally between 18-21oC, avoid heating the property for short periods as this will reduce its moisture buffering ability.
When showering or bathing keep the door shut and the area heated and ventilated until its dry.
Avoid drying clothes within the building, if you must, keep them in one room, which is heated and ventilated. A dehumidifier may be of help if you are unable to ventilate fully.
Check that you have the correct type of extractor fan in the bathroom and kitchen/utility room , ideally it should have a continues run setting or humidity control sensor (set at <60%RH). If you have no mechanical ventilation, then a damp control ventilation fan should be considered.
Open window trickle vents where fitted (but not in the room with a extractor fan).
Repair any defects which allowing water to penetrate the building fabric or any plumbing leaks.
Clean and dry any mould affected surface (which is less than 1m2) immediately. Larger affected areas may need professional cleaning. Use an anti mould emulsion paint may be of help in sever situations.
Wash all affected clothing in a >50˚C wash to control mould (check labels for suitability).